This circuit was obtained from Elektor magazine and published in the Encyclopedia of Electronic Circuits Vol 5 of 1995. Transistors are RF types that are still common today.
This circuit was obtained from the Radio Electronics magazine of October 1960. The circuit uses a...
Found in an Electronics World of 1966, this circuit makes use of FETs of the time. Modern...
Found in a 90s 303 Circuits, this circuit triggers a load from a 50 mV audio signal. When the...